An expert on the law of evidence, Professor Wellborn played a key role in the drafting of the Texas Rules of Evidence. He is the author or co-author of several books, including Cases and Materials on the Rules of Evidence (St. Paul: Thomson/West, 6th ed. 2012), Courtroom Handbook on Federal Evidence (St. Paul: Thomson/West, 2014 rev. ed.), and Cases and Materials on Torts (St. Paul: Thomson/West, 4th ed. 2011), as well as the author of a number articles, including "Demeanor" (Cornell Law Review, 1991). He has been a Visiting Professor at Harvard Law School.